Generally, in a smart key system, a wireless transceiver is mounted on a card key that a user carries. When a user carries the wireless transceiver mounted on the card key and enters into a vehicle, the wireless transceiver communicates with a control unit disposed in the vehicle.
Even when a user merely carries the card key, the wireless transceiver locks/unlocks a vehicle door, starts an engine, or allows the other operations to be performed.
The card key includes a circuit board in which a circuit part is mounted on a resin case of synthetic resins, and a battery is mounted as a power source on the card key.
Moreover, the card key includes a mechanical key that is used when the discharge of the battery, the damage of the wireless transceiver, or a situation similar thereto occurs.
The mechanical key is placed in a hollow space of the resin case.
In an emergency, a user takes out the mechanical key from the hollow space of the resin case, and uses the mechanical key for locking/unlocking or for the other operations.
Recently, the smart key system requires an information exchange system that uses a more number of components and is more complicated, and the card key is required to become thin and small so as to enable a user to easily carry the card key.
Korean Patent Publication No. 10-2012-0006949 discloses a related art vehicle card key that is as illustrated in FIG. 1.
FIG. 1 is an exploded perspective view of the related art vehicle card key. FIG. 2 is a description view illustrating a mold used to manufacture the related art vehicle card key of FIG. 1.
As illustrated in FIGS. 1 and 2, the related art vehicle card key includes a key body 10, a circuit board 31, and a sheet member 20.
The key body 10 is formed of a resin material by insert molding.
An electronic component 32 for wireless communication is mounted on the circuit board 31, which is coupled to one surface of the key body 10.
That is, as illustrated in FIG. 2, when the circuit board 31 has been disposed at a top of a lower mold 61, resin is charged into a cavity 62a, thereby forming the key body 10.
In this case, since the circuit board 31 is disposed at the top of the lower mold 61, when the key body 10 is formed by charging resin into the cavity 62a, the charging of the resin into the cavity 62a is completed, and then a rear surface of the circuit board 31 is exposed to the outside of the key body 10.
Therefore, in the related art, the sheet member 20 that is formed separately from the key body 10 is adhered to the other surface of the key body 10, thereby preventing the circuit board 31 from being exposed to the outside.
As a method different from this, there is a method in which a mold fixing part is formed in a circuit board in order for the circuit board to be disposed in a space between a lower mold and an upper mold, molding of a key body is completed, and then the mold fixing part is removed.
In this case, however, the mold fixing part is removed, and a subsequent process such as a spray process is needed for the removed portion not to be exposed to the outside.